Kaldor City is an audio drama CD series that will appeal to fans of dark, political SF with a sense of humour. Careful, complex plotting, witty dialogue and superb acting create a picture of a corrupt society that is about to face a challenge to its very existence -- with no guarantee of success. All this and some brilliant action sequences too.

The series uses characters and a setting first created for the Doctor Who story "The Robots of Death," but it's not necessary to be familiar with either the TV episodes or the sequel novel Corpse Marker to follow the story, as the writers have done an excellent job of weaving necessary backstory into the scripts. In fact, for the first three CDs it's possible to consider it as a completely independent universe with no relationship to Doctor Who. This isn't surprising, as Kaldor City is an independent production using only the original characters and setting which were copyrighted to scriptwriter Chris Boucher, not the BBC-held material. Unfortunately, the final two CDs draw on another Doctor Who story by the same scriptwriter, and do so to such a degree that I think it might be difficult to understand all of what's happening in the fifth CD unless you're familiar with that story.

There's an overall story arc, with each episode building on the previous one, and an impressive cliff-hanger at the end of episode 4. Nevertheless, it's possible to enjoy the first CD as a standalone play, so it's well worth trying the first to see if you like the style -- you won't be left dangling, needing to buy the next CD to find out how the story in episode 1 is resolved. Episodes 2 and 3 are also reasonably self-contained, although it will pay to listen to the CDs in order, and it's quite feasible to enjoy the first three on their own without ever listening to 4 and 5. I have no hesitation in recommending the first three CDs to a general SF audience. The fourth and fifth are more problematic, given the references to the Doctor Who source material. For those who do need to go back to the source to understand what's happening, the relevant story is available on video and as a novelisation, though not yet on DVD.

Kaldor City is the capital of a planet colonised so long ago that most of the population are unaware that their culture originated elsewhere, or that there are other inhabited planets. This is in spite of the fact that the planet is largely storm-swept desert and not really habitable without life support equipment. Much of the manual work is done by robots, to the point where humans are outnumbered by humanoid robots. The series explores the psychology of such a society, and how the stresses produced by such conditions can be manipulated for political gain.

The planet is governed by the Company, an organisation largely run by a hereditary aristocracy. The current Chairholder, Uvanov, is a man who rose from the ranks, to the disgust of many of the Board members. It doesn't help that he's keen on reopening contact with the outside universe, something he sees as likely to shake up the class system. He's intelligent, ruthless, and cunning, qualities he needs to survive his enemies' attempts to depose him. Paranoia is an asset rather than a drawback.

His rise is partly due to being one of the few survivors of the Storm Mine Four incident. Storm Mine Four was one of the giant mining machines that go into the desert for months-long tours of duty -- a suitably isolated place for a mad genius to experiment with turning ordinary domestic robots into killers. Taren Capel was killed and his aberrant robots destroyed, and the episode was hushed up. How could a society so dependent on robots deal with the knowledge that robots can, after all, kill?

Capel considered robots superior to humans, and wrongfully enslaved. His intention was to kill the human population and "free" the robots. This has been twisted by a religious anti-robot group, who believe that Capel was actually anti-robot and was turning them into killers to force the Company to stop using them -- the robots are an effective way to keep the working class under control, not through violence (robots cannot harm humans, or so most people believe), but through withdrawal of the privilege of a job.

Such groups are ripe for use by those trying to score political points. The series follows the struggle for political control in Kaldor City, and what happens as events start to slip out of the control of those who initiated them. It slowly becomes clear that the manipulators are themselves being manipulated, in a complex, multi-layered story. Along the way there are some excellent show-don't-tell demonstrations of how mob psychology and the media can be used for political gain.

The first episode, "Occam's Razor," introduces the characters and setting. Uvanov has a problem. Someone is killing members of the Board, and sending the corpses to him. He might be next -- and even if he isn't, if he doesn't solve the murders he's likely to be relieved of his position as Company Chairholder. His allies include a collection of thugs euphemistically called a security team, and Firstmaster Carnell, a psychostrategist. Carnell has a profound understanding of human psychology, and for a fee will devise a strategy that will manipulate people into the actions his client desires.

Uvanov acquires another asset -- Kaston Iago, a professional assassin who is initially suspected of the murders. After that little misunderstanding is cleared up, Iago agrees to work for Uvanov as a security consultant. Between them, Carnell and Iago solve the murders to Uvanov's satisfaction. They're also solved to the satisfaction of Carnell and Iago, although for slightly different reasons.

The second episode, "Death's Head," was written by Chris Boucher himself. It opens with a lecture on psychostrategy from Carnell. Carnell is as smug and patronising as ever, which means he's quite happy to explain to his employers all about how the latest strategy worked, and why it's their own fault it didn't work quite as they'd wanted. Or rather, almost all -- a psychostrategist has to keep some of his strategies secret, doesn't he?

What is the connection between a rebel arms cache, an isolated research station, and an attempt on Uvanov's life? With Carnell involved, there has to be one; but with Carnell involved, the answer is likely to be on the baroque side. In the end, nothing very much has happened after all, but it's happened very entertainingly. Boucher deftly weaves together several plot strands, each providing a glimpse of the harsh reality that is life in Kaldor City, while quietly setting up the next story.

The political game continues in the third episode "Hidden Persuaders," but now the stakes are getting higher. The Tarenists have resorted to violence, and more than one faction is pulling their strings.

The Tarenists are dangerous but Uvanov isn't above using them for his own purposes. Uvanov doesn't have anyone inside the sect, but he has something almost as good -- Blayes, a former security agent, is now working for the Tarenists, and Carnell can predict her behavior using her personnel records. This makes her almost as valuable as an actual double agent, so when a Tarenist raid on Oxygenator Four goes wrong, Uvanov wants her protected, whatever the cost.

The fourth episode, "Taren Capel," starts off simply enough, picking up one of the loose ends left dangling at the end of Hidden Persuaders. Who arranged for a tiny payroll deduction to the Larson project, and why? Security Chief Rull's investigation sets in motion a chain of events that make it clear that the political game in Kaldor City is now out of the control of the known players.

Iago and Carnell, in their different ways, try to understand events rather than simply reacting to them. Unlike most of the population, they have a way to escape the planet, but only as a last resort -- both men are refugees from the galactic empire, with good reasons not to go back. Iago, in addition to the art of murder, knows a thing or two about robotics. He works out how Capel was going to murder the entire human population of the planet. . . and that the plan isn't over just because Capel's dead.

Carnell's training allows him to remain detached and study what's happening. It's become clear to him that someone or something has been manipulating them all, including him. The clues he uncovers lead to secrets in the Company's archives, but a direct attack pushes him into leaving before he can pursue his investigation further. He leaves some of his new knowledge as a parting gift to Uvanov and Iago, but it's a gift that they, and everyone else in Kaldor City, will regret receiving: dig up enough of the past, and even the dead can speak.

The final episode, "Checkmate," brings together various storylines and clues from previous episodes, with Uvanov and Iago fighting for both their personal careers and the lives of everyone in the city. Something very old and very dangerous has been behind the events of the past year -- can its plans be stopped?

I found the ending slightly disappointing, in part because the series had made such a strong start as an independent SF drama before going back to being a spin-off, and one requiring knowledge of a particular story. Even so, I don't regret the time and money spent on listening to this series.

Yes, I liked it -- a lot. It has what I want in an audiodrama: a strong script with complex characters, performed by an excellent cast. (For those familiar with the TV episodes, the CD series uses the original cast.) Since this is audio, it's also possible to have high quality special effects on a low budget; but unlike most current TV SF, the effects are there to support the script, rather than being the most important aspect of the show. I'm tired of "SF" commissioned by TV executives who think that flashy FX, skimpy costumes, and big tits/muscles are all that's needed to satisfy an audience. Nothing wrong with those, as long as they're the icing on the cake, but all too frequently the cake is a cardboard mock-up, there only to display the icing. Kaldor City is written and produced by people who obviously feel the same way I do. It's the real thing, and worth every penny of the price.

Kaldor City is available in SF shops, and directly from the production company. There's an order form and list of retailers (including several online shops) at their website.

The series is in part an homage to the work of writer Chris Boucher, who worked on several British SF shows in the 1970s and 1980s. For those who are interested, the source materials are:

• Doctor Who: The Robots of Death. Four TV episodes written by Chris Boucher, available in VHS and DVD formats, and as a novelisation by Terrance Dicks.

• Doctor Who: Corpse Marker. Novel by Chris Boucher.

• Doctor Who: [title withheld]. Knowing which story this is would be a spoiler, so resist the temptation to peek! Four TV episodes written by Chris Boucher, available on VHS and as a novelisation by Terrance Dicks.

• Carnell is a character originally created by Boucher for the episode Weapon in the BBC series Blake's 7 (currently available on VHS, DVD available soon), and it's strongly hinted that Iago is another character from that series. It's not necessary to know anything about them other than what's given in the Kaldor City series.

The characters originally created for TV episodes are played by the original TV actors, and several of the other actors also appeared in those shows or Chris Boucher's Star Cops.

Jules Jones (email: jules.jones@myrealbox.com) is a materials scientist who by rights should be writing hard SF, not the mutant offspring of political SF and gay porn that was the only royalty-generating writing until now. Examples may be found at JulesJones.com, along with musings on ancient and modern British SF shows. The payment for this review will be used to acquire further source material for the latter.